Why Does a Tooth Crack?

A tooth that is cracked can be painful.  Sometimes, it can be hard to tell which tooth is the source of the discomfort and often the crack cannot be seen on an x ray.  Patients often ask what caused their tooth to crack.  The most common reasons a tooth may develop a crack are:

• Loss of tooth structure due to large fillings which can exert outward forces on the remaining tooth structure
• Frequent chewing on hard foods such as ice, hard nuts or hard candy
• Grinding or clenching your teeth
• Teeth that have had a root canal that have not been permanently restored and are brittle

A cracked tooth may hurt because the pressure of biting causes the crack to open. When you stop biting, the pressure is released and the pain goes away.  Even if the crack is too small to see, when it opens, the pulp inside the tooth may become irritated.  The pulp is the soft tissue inside the tooth where the nerve and blood vessels are located.  If the crack irritates the pulp, the tooth may become very sensitive to hot and cold.  If the pulp becomes diseased due to the crack, a root canal (endodontic treatment) may be necessary to save the tooth.

The most common symptoms of a cracked tooth are:

• Sharp pain when biting down but then quickly disappears when not biting
• Extreme sensitivity with hot and cold

Sometimes upon visual examination, the dentist can see a crack in a tooth, but the patient has no pain or sensitivity.  This means that the crack has most likely not yet penetrated the tooth enamel, but in most cases, eventually the crack will penetrate deeper into the tooth and the patient will begin to have sensitivity.

Treatment for a cracked tooth depends on the size and location of the crack.  Sometimes the crack can be repaired by replacing an old filling.  If the crack cannot be repaired by a filling, then placing a crown (cap) over the entire tooth protects the tooth from further damage.  Unfortunately, sometimes the tooth is too severely cracked and must be extracted.

A cracked tooth can become a bigger problem if it is left untreated, not to mention painful every time you bite down on something.  If you think you may have a cracked tooth, it is important to have an exam by your dentist.